package com.example.common.utils;

import org.apache.shiro.cache.Cache;
import org.apache.shiro.cache.CacheManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Iterator;
import java.util.Set;

public class CacheUtils {
        private static Logger logger = LoggerFactory.getLogger(CacheUtils.class);
        private static CacheManager cacheManager = SpringContextHolder.getBean(CacheManager.class);

        private static final String SYS_CACHE = "sysCache";

        /**
         * 获取SYS_CACHE缓存
         * @param key
         * @return
         */
        public static Object get(String key) {
            return get(SYS_CACHE, key);
        }

        /**
         * 获取SYS_CACHE缓存
         * @param key
         * @param defaultValue
         * @return
         */
        public static Object get(String key, Object defaultValue) {
            Object value = get(key);
            return value != null ? value : defaultValue;
        }

        /**
         * 写入SYS_CACHE缓存
         * @param key
         * @return
         */
        public static void put(String key, Object value) {
            put(SYS_CACHE, key, value);
        }

        /**
         * 从SYS_CACHE缓存中移除
         * @param key
         * @return
         */
        public static void remove(String key) {
            remove(SYS_CACHE, key);
        }

        /**
         * 获取缓存
         * @param cacheName
         * @param key
         * @return
         */
        public static Object get(String cacheName, String key) {
            return getCache(cacheName).get(getKey(key));
        }

        /**
         * 获取缓存
         * @param cacheName
         * @param key
         * @param defaultValue
         * @return
         */
        public static Object get(String cacheName, String key, Object defaultValue) {
            Object value = get(cacheName, getKey(key));
            return value != null ? value : defaultValue;
        }

        /**
         * 写入缓存
         * @param cacheName
         * @param key
         * @param value
         */
        public static void put(String cacheName, String key, Object value) {
            Cache<String, Object> cache = getCache(cacheName);
            cache.put(getKey(key), value);
        }

        /**
         * 从缓存中移除
         * @param cacheName
         * @param key
         */
        public static void remove(String cacheName, String key) {
            getCache(cacheName).remove(getKey(key));
        }

        /**
         * 从缓存中移除所有
         * @param cacheName
         */
        public static void removeAll(String cacheName) {
            Cache<String, Object> cache = getCache(cacheName);
            Set<String> keys = cache.keys();
            for (Iterator<String> it = keys.iterator(); it.hasNext();){
                cache.remove(it.next());
            }
            logger.info("清理缓存： {} => {}", cacheName, keys);
        }

        /**
         * 获取缓存键名，多数据源下增加数据源名称前缀
         * @param key
         * @return
         */
        public static String getKey(String key){
//		String dsName = DataSourceHolder.getDataSourceName();
//		if (StringUtils.isNotBlank(dsName)){
//			return dsName + "_" + key;
//		}
            return key;
        }

        /**
         * 获得一个Cache，没有则显示日志。
         * @param cacheName
         * @return
         */
        public static Cache<String, Object> getCache(String cacheName){
            Cache<String, Object> cache = cacheManager.getCache(cacheName);
            if (cache == null){
                throw new RuntimeException("当前系统中没有定义“"+cacheName+"”这个缓存。");
            }
            return cache;
        }
}
